Insights into Effects of Combined Capric and Lauric Acid on Rumen Bacterial Composition.

This study used next-generation sequencing to assess the impact of combined capric acid (C10) and lauric acid (C12) on the ruminal bacterial composition. Eight Holstein cows were randomly assigned to two groups using a cross-over design. The cows were fed two silage-based diets with the addition of either 100 g of stearic acid per cow per day (control), or 50 g of capric acid and 50 g of lauric acid per cow per day (C10 + C12). On day 18, 250 mL of rumen fluid was collected from each cow, and DNA was isolated, amplified, and sequenced. Treatment did not alter bacterial diversity indices, the relative abundance of archaea, nor the fiber-degrading microorganisms, except for a decrease in Fibrobacter (from 2.9% to 0.7%; p = 0.04). The relative abundance of Prevotellaceae decreased (from 39.9% to 29.6%; p = 0.009), which is notable because some members help to efficiently utilize ammonia by releasing it slowly into the rumen. Furthermore, the relative abundance of Clostridia increased (from 28.4% to 41.5%; p = 0.008), which may have aided the increased ammonia-nitrogen levels in the rumen, as this class contains hyperammonia-producing members. Our study reveals alterations in bacterial abundances with implications for rumen ammonia levels, offering insights into potential strategies for modulating rumen fermentation processes and methane production in ruminant livestock.

Combined effects of nitrate and medium-chain fatty acids on methane production, rumen fermentation, and rumen bacterial populations in vitro.

This study investigated the combined effects of nitrate (NT) and medium-chain fatty acids (MCFA), including C8, C10, C12, and C14, on methane (CH4) production, rumen fermentation characteristics, and rumen bacteria using a 24 h batch incubation technique. Four types of treatments were used: control (no nitrate, no MCFA), NT (nitrate at 3.65 mM), NT + MCFA (nitrate at 3.65 mM + one of the four MCFA at 500 mg/L), and NT + MCFA/MCFA (nitrate at 3.65 mM + a binary combination of MCFA at 250 and 250 mg/L). All treatments decreased (P < 0.001) methanogenesis (mL/g dry matter incubated) compared with the control, but their efficiency was dependent on the MCFA type. The most efficient CH4 inhibitor was the NT + C10 treatment (- 40%). The combinations containing C10 and C12 had the greatest effect on bacterial alpha and beta diversity and relative microbial abundance (P < 0.001). Next-generation sequencing showed that the family Succinivibrionaceae was favored in treatments with the greatest CH4 inhibition at the expense of Prevotella and Ruminococcaceae. Furthermore, the relative abundance of Archaea decreased (P < 0.05) in the NT + C10 and NT + C10/C12 treatments. These results confirm that the combination of NT with MCFA (C10 and C12 in particular) may effectively reduce CH4 production.

Acceptability of AAI from the Perspective of Elderly Clients, Family Members, and Staff-A Pilot Study.

Although animal-assisted interventions (AAIs) are increasingly part of comprehensive rehabilitation and many of its effects are already well described, the methodology for performing AAI depends on the specific patient, animal, and treatment objective. Acceptability of AAI from all involved members is a little explored area. Thus, 214 respondents (32 AAI clients, 146 family members, and 36 healthcare and social care workers; 98 males, 116 females; mean age 46.3 years (±16.5 SD)) completed a list of statements focused on AAI with a dog. This list was distributed directly in nursing homes, retirement homes, and in households with home hospice care. All statements were rated on a Likert scale of 0-3. The results show that AAI is generally very well received, with over 90% of respondents considering AAI to be beneficial. The perception of AAI and trusting the handler with their dog was evaluated very positively, as well as possible concerns about hygiene. The results were in many cases affected by demographic factors of the respondents (age, gender, role in AAI, education, and size of settlement). It seems appropriate in future studies to focus on the attitude of individual groups, and thus advance the methodology of implementing AAI.

Effect of Dog Presence on Stress Levels in Students under Psychological Strain: A Pilot Study.

As university students face many stressful situations, especially during the examination period, this study focused on the use of animal-assisted activities (AAAs) with a dog as a means of relieving students' stress before a final exam. The aim was to determine whether a 10-min interaction with a dog affected subjectively evaluated stress and mood, objective blood pressure, and heart rate. Ninety-three female students (mean age = 22.5 years; standard deviation = 3.8 years) were divided into three groups according to their preference. The first group underwent AAAs (n = 26), the second group chose a relaxation technique (n = 28), and the last one was a control group (n = 39). Physiological values were measured using a pressure gauge and the subjective feelings of stress and mood were evaluated by the Likert scale 1-5. The AAA group showed significant improvement after 10 min of interaction in both mood and stress, with no change in heart rate and blood pressure. The remaining groups showed a significant decrease in blood pressure, but not in heart rate, with different evaluations of mood and stress. AAAs with a dog appear to be effective in improving students' mood and stress without affecting their physiological parameters.